SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eafecbba2878cf515091e32b52833fa8687363d3b113dc5ac830ef08ca3cf631' 
  AND token = 'XwypyqQxg5nXA+yWPXCW+kFkPQAaNvz8j60nzoBVTfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}